You can sign up for each of the 36 leaderboards, so you can win in multiple categories and actually amass quite a respectable amount of premium time and boosters. Each leaderboard will have 4,000 places with rewards (see above), so in total there will be 144,000 rewarded places.

Please also bear in mind that:

There are some less popular nations and tiers which give you even higher chances to win thanks to smaller competition.

Compared to last year, leaderboards are not per vehicle, but per nation-tier, opening more chances to people who don't have as many tanks in their garage

You no longer need to get five great consecutive battles. Just play and each battle better than previous ones will improve your end result.

I hope you guys will have a lot of fun going for those prizes and I'll see you in-game